Sometimes when I withdraw BTC to my wallet, I set really low fees like 50-70 satoshi per byte and wait for weeks, because I'm not going to spend those coins in the near future anyway. I think it's a good way to save a bit of money, because if you look back, you might realize that your fees have added up to a big amount in USD value, while it wasn't always necessary to get those coins confirmed asap.
So, do you use low fees, or always want to get confirmation in a next few blocks?
I don't usually do this because when I sell my bitcoins, I always compute the transaction fees within it even if the price is ridiculously high. The only time I sell bitcoins is the time when I really need the money and time most so selling it with a high amount of dollar per byte is fine with me.