I think it's natural that people will be encouraged to play more loosely when they know they can rebuy - sometimes this is a good thing, sometimes it's not.
Our local casino runs a rebuy tournament once a week - $25 buy-in, $25 rebuys for the first hour, but you're allowed to rebuy (for either $1000 or $2000 in chips) any time you got below your starting stack of $1000. So you could pay your blinds for a round, or lose a minimum bet in a hand, then throw fifty bucks at the dealer and be up to almost $3000 in chips.
It's clearly a strategy for the casino to make money from all the rebuys, and it works. The solid / tighter players have the potential to make a lot of chips from all the donk shoves though.
I deal a bar game that has rebuys and tends to work a bit better because people have to get felted before they can buy back in (at the starting stack). It still encourages donk shoves to a degree, but they've got to do it with the knowledge that they'll be starting back with a less competitive stack. And the solid players still have an opportunity to accumulate chips from the "I'll just rebuy if this doesn't work" players