I really don't see why teachers would or should contact the sub. The sub came to do a job, it was done, they get paid, that's it. I have always left my phone number and email address for them to contact me if they have questions (as a common courtesy) and if they needed me again, but I have never ever received a follow up for the good job I've done.
I wasn't looking for one, either.
When I ran into the teacher on another day, they would thank me a lot of times, but even then, the following week that one day must have seemed like it was 2 years before.
The best compliment a sub can get is a repeat request, a referral, a recommendation to the P or all of the above.