Free Chip, Free Spin and Demo Play Odds????

I know it's hard to tell, but do certain casinos/game providers adjust the odds to make them seem more favourable and hitting more bonuses  while using a free chip or spin bonus,  or during demo play?

Who sets the odds for casinos, demos and bonuses (if they can be different), is it purely the game developers, or can different casinos adjust the odds of particular games (I know the answer to that I reckon, yes, most definitley). 
I'm more interested in whether people think the casinos give the users bonus and demo plays with improved odds to lure players in???

To be honest, I've always wondered about this too, the difference between fun mode and real mode is very big, even with identical bets (in fun mode we usually increase the bet) but I tried with small bets and the difference is huge, I don't know if there is an obligation for the fun mode to have a certain RTP but that makes us think about it

i tried to time demo plays with real plays and so to say i learnt a lesson that it is a formula to gift casino money

They have absolute and complete control over their establishments. (COMPLETE).

Has anyone noticed that in the tournament play of certain casinos, the random jackpot hits now and again. I have yet to experience such a thing during regular play. Nor have I heard of anyone else winning a random jackpot ever!

For the newbies out there, have fun playing, but learn as much as you can along the way.

I have been trying out a lot of the casino slot thats I normally would not play but they were offered as a demo here on LCB and I have found myself wondering if the payouts are anything like they would be if I was spinning the game in real play. Some of the demo games ended up with some pretty epic payouts so I have thought about this as well.