Doc overestimating human willpower makes no sense

So let's talk about slightly 'different' story. Let's say the Libyans take weeks longer to realize they've been duped, or in any case, don't find Doc or whatnot. So Doc is not in any danger at all.

This would mean Doc's plan to go to the future would work. He timetravels to go see who wins the world series, then comes back.

Then what? What would his plan be after what? The REASONS and MOTIVATIONS for time travel we see in this movie are all based on NECESSITY, not volition.

What if Doc COULD freely decide to do whatever he wants, time travel-wise? Would he lend it to Marty sometimes? Would Marty lend it to his family members or friends?

In any case, let's say Doc decides not to time travel after he gets his 'future fix'. He goes to 2010 or whatever, sees who wins the world series, then comes back and tries to live a 'normal life' (as if anyone could, Marty would consantly bugger him about letting him time travel, I am sure, but let's put that aside).

Now, we know Doc had to lose a lot of money, invest most of it to 'realize his vision', so he's probably pretty poor, besides his lab, garage and equipment.

We can EASILY imagine a situation, where Doc ends up in financial trouble and problems.

He knows a lot about who wins things, after he has seen 'who wins the world series' in the future (though why would a science-nerd be into SPORTS is another hollyweird myth, everyone has to somehow love sports in these movies), and of course the corporations that have become enormous and wealthy, but might be very small in 1985.

Now, he sits sipping his morning coffee, talking to the dog, whose psychology he doesn't understand (like most people), reading all the bills and 'due' letters and what have you, feeling depressed because of all this financial trouble, burden and problems. He's going to be bankrupt!

Unless...

You get my point? People of this world are easily tempted. They are not iron-willed. A hungry child can't spend 5 minutes next to a chocolate bar, even if he's promised two chocolate bars after the 5 minutes is over.

Think how _UNBELIEVABLY_ tempting it would be to use his future knowledge in 1985, 'just a little bit', 'just enough' to get through his money problems. Think how SUPER-willed the Doc would have to be to NOT use that knowledge at all, while he's sinking in financial problems and can barely feed his dog anymore.

Why would he TRUST that he can do that? Why would he take it as a GRANTED that he could just happily ignore these ENORMOUS temptations to get wealthy and rich SO easily and seemingly harmlessly? I mean, the doc might not be greedy, but even he must lust for more lab equipment and all kinds of technology that's just becoming more and more interesting in the eighties and is only going to get more efficient, complex and interesting to a 'scientific mind' as the time passes.

How long could doc hold out without succumbing to the temptation to making at least a tiny 'bet' he knows he would win? Buying just a few stocks of a corporation he knows will become super big in the future?

Doc clearly overestimates his own and other people's willpower to resist temptation. With enough temptation, anyone will succumb, unless they are some kind of enlightened Zen master, or at least meditate quite a lot every day and basically live in Zatori or something.

I wouldn't blame anyone for succumbing to ever-increasing temptation like that, and Doc shouldn't expect anyone to be able to resist such forever. Yet he happily travels to the future without even considering any of this? He's BOUND to change history by bringing future knowledge into the past. Does he plan to erase his own memories somehow?

What was his plan, really, when the temptations keep pounding him at the back of his mind with ever-increasing power every day, and his bank keeps harassing him more and more about missed payments and bills that are due that he simply can't pay? Something's got to give, and he trusts his own willpower too much.

It's like Newman and fleas in Seinfeld - no matter how much willpower you may have, it won't matter, because the temptations keep crawling and biting at you and creating insane thoughts until you accept that you have to succumb to them, the pressure would increase every waking moment, maybe even creating insomnia and stress that would make Doc insane.

I am not talking about the so-called sequels here, but if I was, that whole 'I didn't invent time machine to blah, I invented it for 'no reason' ('traveling through time' is not a reason to invent a machine that can travel through time - it's like saying you have a car so you can ride a car) is really Doc being optimistic about Marty's willpower.

I mean, Marty did look at some of those results, he knows QUITE A LOT about 2015's reality already, does Doc really trust that he wouldn't use that knowledge at all for his personal gain whatsoever, especially with a gorgeous girlfriend to feed? (And I am talking about Claudia Wells)