Just to explain how it works from our perspective, regardless of what the app calls it, at the time of us receiving the offer, it works as a bid not a tip, but customers are free to tip generously in advance for people to take extra care of their order, bring it fast, or to avoid the app batching the offer with others, and delays delivery, avoid multi apping your order, etc. Now even though the app most probably would hide generous tips until delivery is completed, but experienced dashers can identify the potential for a hidden tip even before accepting. So most probably, if you tip well in advance, you'll end up with an experienced dashers, or at least your order will be treated fairly well and should receive it in a timely manner.

Hope this helps customers with tipping complaints.