Pros
Friendly coworkers / good team atmosphere. Many reviews say the other staff are kind, helpful, and easy to work with. Flexible scheduling (especially for part-time/students). They often can adjust to personal commitments. Employee discounts. The store discount is often mentioned as a good perk. Variety in tasks / not just standing at checkout. You might get to stock, assist in production/donation processing, help with pricing or organizing, etc., which adds variety. Good benefits for full-time or more senior employees (in some locations). Some reviews note benefits, paid leave, etc.
Cons
Work can be physically and mentally demanding: lots of standing, dealing with messy/dusty items, cleaning, sometimes dealing with difficult customers, repetitive tasks.