Yeah! It's not normal at all.
But I will say that on my recent SFO-PHL leg the FA in F did ask the two 20-something guys, that clearly announced they upgraded, to reframe from placing their feet on the bulkhead. They were cool and said "Totally! We're in First and I get it!".
A few smirks were had by me and my seat mate. The rest of the trip was amusing enough watching the FA help them with adjusting their seats and taking their pictures during the flight.