You hear this twaddle all the time. How can total strangers "love you"? They know nothing about you, and vice-versa.
I equate this with the very similar nonsense that crept in some years ago, people starting off a conversation with "How are you"? I've noticed that when I answer "Well, I had shingles last year, the marks are very slow to go, I've had a couple of bouts of the runs in the last month or two, just lately I've had some crippling sciatica, especially at night, makes sleep almost impossible, and, oh, I think I've now got a second hernia" . . .the person who asked "how are you" doesn't seem that interested. In which case, don't bl**dy well ask?!
I'll add on to this daft trend with another one, people saying "do have a lovely day" as they depart, or end a phone call, or as you pay in a shop. Even the TV newsreaders say "do enjoy the rest of your evening" . .that's at 10.30pm, so hardly much time left?! I couldn't give a rusty fart how THEIR day is going -- did this nonsense come from America, and we're limp enough to have copied?