I had a SimpleHuman Sensor trashcan that needed batteries. I seldom had to replace them and it lasted at least 10 years before a piece on the lid broke.
I replaced it with one I got at Sam's Club (different name but actually the parent company of SimpleHuman) and I've had that one at least a year. Use it multiple times a day and haven't had to replace the batteries.
I'd say something is wrong with yours.
"" A little learning is a dangerous thing."-Alexander Pope