Poker does not have to be all about Gambling, any more than Snap is considered Gambling. Sure you can put side bets on Snap! Just like you can turn two raindrops falling down a window pane into a bet, winner taking all, but it doesn't have to be like that.
I suppose this is one reason I prefer Tournament Poker over Cash games, in a Cash game every chip you put into a pot is
real money out of your pocket, In a Tournament, every chip is a fraction of your Buy-in and yes it can be considered to be gambling.
I prefer to think of the buy-in as the price I pay, to play a game I enjoy, just the same as paying an entrance fee to watch a football game, or a film at the Cinema, It is nothing more than the fee I pay for an evenings entertainment.
The only difference is at the end of a film you go home with slightly less money than you went out with, but with poker you can go home with your money back and more if you win, but if you go home with money in your pocket with just the buy-in missing, where is the harm? You have had an evening out, at a price you are willing to pay.
When the fun Stops, STOP!