Y’all are looking at this wrong. People going all-in preflop with a disproportionate amount of hands are the best! Seek them out! You have someone playing badly, making obvious strategic mistakes. This is your opportunity to exploit their mistakes.
Sit back, let them take a few blinds, keep your own stack relatively topped off (so that when you win you get the max), and when you get a decent hand call the all-in and play along with them. You’ve got a hand that beats 2 random cards 60-80% of the time…you just have to embrace the variance.
You may very well get stacked a couple times when they suck out or happen to have a good hand, but if you can’t afford to get stacked a couple times you’re not managing your bankroll well and should move down in stakes (if it’s 1-2, I can’t help you, other than the site reloading you).
If they are going all-in every hand (2 random cards), and you play hands that are in the top 10-20% you will come out ahead in the long run, so long as you understand and accept the variance. For example, if you play 77+,A9s+,A5s,KTs+,QTs+,JTs,ATo+,KTo+,QJo that’s about 15% of hands and you should win 65% vs 35% for the villain playing 2 random cards. That’s almost 2:1 in your favor. If they are only doing it on occasion, but more than they should, tighten up and do it with the top 10% (77+, all suited broadways, AJo+, KQo). That still beats someone shoving 1 out of 3 hands better than 60% of the time
It’s best if you can sit directly on their left so you’re almost always in position, but even if you play out of position, just make sure you limp-fold a hand every once in a while (so they don’t immediately shut
down whenever you limp with a good hand) and call them down.
This is the one case where you should be limping. Don’t bet into them because they may shut down if they think your strength means you’re going to call them with the goods. As the saying goes, “Never interrupt your enemy when he is making a mistake.”
Soon enough this player will give away all their chips if they don’t change their play. You want to be on the receiving end when they do as much as possible.
Once they lose all their chips you can go back to your friendly game of limpypoo-let’s-have-7-players-see-a-flop.