There's a difference. If a gift is broadly offered, then it's usually not a problem. I've looked at lots of examples of that over the years. If you invite all of the MPs to something or other, that's fine, but if you target some of them....
Another thing I want to say is that people are always talking about lobbyists. The act that I administered doesn't focus on lobbyists: it focuses on stakeholders, and they're a much broader group than just lobbyists. Just remember that just because you're not a lobbyist doesn't mean you're not necessarily caught.