hiring people during busy times and finding reasons to fire just before the 90 day probation is up

Maybe you’ll hate me too but I wish they did more of this or target different employees. There have been years where I needed some extra income and looked for a short term job without success. I kept getting the response that I was too likely to leave after the seasonal rush, but don’t they need some amount of that? Give a regular employee more hours, but fill your seasonal rush with people looking to work for just the season