Agree that there's a big difference between frugal and stingy. As other posters have pointed out, people who are stingy are very often mean in other ways too. And take great pleasure in getting one up on you which can be very hurtful. I have one relative who is very mean (but not poor in any way) and it does jar that meals we cook for them are never reciprocated. We joke that you have to bring your own tea bag when you visit because you won't be offered a cuppa.
I tend to be frugal, but would hate to be thought of as mean. This thread has me worried! I try to make sure that I have plenty of money budgeted for nights out, so I don't look like I'm watching the pennies. But I would try to suggest a free or lower cost option if someone suggested a last minute expensive meal or whatever.
I also try to give my time generously and do things for people. I go out of my way to bake a cake, drop off a meal, organise or host get togethers, visit friends who live further away, etc. I don't spend big money, but try to make my loved ones feel special.
I also value experiences, so don't buy huge presents for my nieces and nephews, but I take them to see a play or a show that I think they might like during the year, or bring them to the woods for a day, etc.