I always back in at home and try to back in everywhere else it's desirable. It may not be desirable if I'm socializing out of the back of the truck.I still do at home.
The people that piss me off are the ones that park like they backed into angled parking. They have to drive the wrong way on a one-way lane in order to exit but they don't care.
Even worse, we had a car at our local HEB on a very busy Saturday parked in the closest spot to the door. It was angled, head-in-only parking. He had parked head-in. So what's the problem? When he left, he backed up into the lane of traffic then cut his wheels the wrong direction. After going back and forth a dozen times, he finally managed to get the car pointed the wrong way on the one-way parking lane. By golly, the street he wanted to exit was directly south of him and he wasn't going to mess with this bullshit of backing out and going north for 20 feet before making 2 right turns. That wasn't direct enough for him.
Of course, it was also on the aforementioned busy Saturday with lots of traffic in the lot. In the area right in front of the door, that traffic ground to a halt because of these shenanigans. At least a half-dozen vehicles had to wait for him to get out of the space. Then we had to pull to the extreme right so that he wouldn't hit us head-on. I imagine none of us were any happier than me, which is not happy at all. Clearly, though, the driver didn't care.
Some drivers simply don't notice what's going on around them. I find that difficult to comprehend but it's true.