I live near both so I shop at both. Here's some of my comparisons:
1. Wegmans employees are more knowledgeable and helpful. They never say "I don't work in this department."
2. Tops' brand "generic" goods are far better than Wegmans' brand "generic" stuff. In fact, some of the Tops' brand stuff is better than the competing brand products. Wegmans generic product are always inferior.
3. Tops has tissue paper bags. They don't hold anything more than a loaf of bread without tearing. Wegmans' bags will hold a 12-pack.
4. Wegmans' generally has better prices. But Tops sells a few things Wegmans does not - for example, "Jumbo" microwave popcorn (much better than any other microwave popcorn).
5. Wegmans' specialty pizzas are far superior to Tops specialty pizzas.
6. Tops' fired chicken and whole roasted chickens are much better than Wegmans'.