Responding to Targeting loose calls

Hey I am a multi table sit and go player and have been turning small profits for several months though.
One theme keeps coming up I play 12-15 tables at once and play quite mechanically, yet I find trouble with people who play 3 or 4 tables at once and try to mess with me by putting in re raises or just playing the flops on me.

I cannot see how playing 5 tables at this level is even worth the time, 15-20% ROI is realistic at this level, but that surmounts to $5 profit an hour at the very best. What's the point?

However I digress one thing I noticed is a certain player picked up on the fact that over 90% of the time I am going to fold to a re raise pre flop, thats normally because I raise with JJ-AQ+ in early stages and 99-a10+ in the later stages eg 100/200 when there are 7 or less players. my range can't often take a re raise because often a re raise has QQ+ or AK.

so this guy is re raising me every time I enter a pot it seems.
so I called him off on an all in with 99 for him to turn up a smaller pair and with AJ for him to turn up A9.

loose risky play I know, but if this guy is going to keep coming on my tables and doing this I have to let him know I am not going to let him keep doing this.

I got lucky/ was right these times and did not suffer any horrible beats, but generally are these calls bad plays given the situation and given the fact that I may bump into this player again as his play was based on what he had seen from me in times past. Maybe negative ICM calls can be justified for future benefit.

Ps I hear the argument for shoving but with 2400 chips at the 100/200 level it seems needlessly reckless to me.

you know, poker is not a source of income for everyone out there - some of us play recreationally, and we don't need to make the big bucks. personally, i have never really cared about the money, i play for the fun of it, and the fact that my bankroll grows is just source of pride for me, not income (well, for now, at least). and in addition, playing can be with a learning purpose - playing few tables in order to learn how to play correctly, and then apply the knowledge elsewhere.

people who "figure you out" will start playing your weaknesses, basically with any 2 cards. this is why the absolutely mechanical play is not especially good. perhaps you shouldn't be open-shoving, but against those regular players you either need to make a stand (by reraising/shoving more often - again, not every time), or to accept the losses. make a pick...