See this is where it's confusing to me. What's the difference between anti-competitive and regular business behavior? When I go to X department store, they'll

See this is where it's confusing to me. What's the difference between anti-competitive and regular business behavior? When I go to X department store, they'll happily look up how items are priced on their website for price matching, but they won't look at the website for Y department store to whom they would also price match. Is that anti-competitive? That's a long way around to what level do businesses have to help you in sending you to a competitor?