air pressure in low profile tires

You don't have to regularly put air in low profile tires. Have the tires checked to see if there's a problem - an ill-fitting bead or a nail.

Low profile tires tend to be installed on nicer alloy type wheels. Fancy alloy wheels are highly susceptible to sealing issues as it's easy for them to become damaged and have corrosion form causing leaks around the beads. It's especially bad if those types of wheels are exposed to salt (whether it be road salt or ocean spray).

I also have a 2012 Subaru Impreza Sport Premium, and I have had similar tire light issues from day one.

The first week after I bought it (new) my light came on. Took it to the tire place, they checked the tire and could find nothing wrong with it. Put air in it and I was on my way. Within a couple weeks the light came on again. I took it to the dealership. They checked the tire, said nothing was wrong with it. I protested, they said they couldn't do anything and I needed to take it to a tire place. Light came on again, took it to "the tire place" and again, nothing wrong with the tires. Said I needed to take it to the dealership.

Flash forward 7 years, 108,000 miles. I've had this same issue intermittently through 3 sets of tires. Currently I'm tracking about every 2-3 weeks the light comes on. It's always a different tire, low pressure (mid-20's, should be 30-32). I put air in the offender, and a few weeks later the light comes on again and it's another tire. I currently rent a car whenever I have to drive long distances (I routinely drive 450 miles to my home state and back). I should be able to take my Impreza but I'm so paranoid about the TPS light that I just won't do it.

I agree with the corrosion explanation. My husband currently works for Yokohama tire and that is the feedback he has gotten. We are going to try and get the rims cleaned and treated to avoid the corrosion and see if that helps. Meanwhile I just keep some quarters in my pocket at all times because I know it won't be long before it happens again.