It is super annoying. It's probably like you said, so teams can't just sit high ground behind rax and farm items without risking something. Kinda like how stronger creeps after a rax goes down give less bounty, so teams can't sit back in their base and farm cus lanes automatically push.
კომენტარის დასაწერად გაიარეთ ავტორიზაცია.
Why is the secret shop in the game? The only real balance reason I can find is that because some of the strongest items can only be completed there, defending teams must push out to safely not get picked off while getting their powerful items.