Is it normal for wireless employee to text customer?

Apologies if this isn't the correct category.
Earlier I was at a T Mobile store to get an iPhone. A friendly employee assisted me in that. I didn't think he was being overly friendly or anything, just a guy trying to make a sale. About 10 minutes after I walked out of the store, he texted me saying, "hey, it's _____ from T Mobile. Thanks for your recent purchase. If you need any help with your iPhone lol, let me know :)". I didn't know if I was supposed to respond or not, after some minutes I decided to reply with, "will do, thanks for the help". To which he said, "Have a good night!"

Is this normal for an employee to text a customer? It's the first time I've had it happen there. I've never had a worker message me after a sale before, I've gotten a few phones from there in the past. Same for everyone in my family, never got a text after buying. Could be something new they're required to do as good customer service? If he was attempting a flirt, that'd be cool, I'd pursue it lol. If not, I'll just leave it alone. I already feel rather dumb about it.