Does copay accepts multiple payments? I am a bit confused as to whether copay wallet accepts multiple payments to a single address based on the phrasing "wallet generates new addresses automatically once you use a bitcoin address once"...if tracking is not an issue I suppose the same address can be sent out to several payees right?
Yes, once you have generated an address, you can have people send any number of transactions to that address from then on.  I just tried it with Copay on testnet and it works fine.  

It automatically generates a new address when a transaction arrives, just to encourage you to use fresh ones if possible, for privacy.  But previous ones continue to work indefinitely.

(Interestingly, it generates a new address whenever a transaction is received, even if that transaction was sent to an older address and the previously displayed address hadn't been used at all.)