Most on-chain wallet software has a gap limit of 20, so when your wallet scans the blockchain after address 201 with an addition of 20 wallet addresses(up to 222), it will stop searching at 223 when it found nothing on the address. You have no problems displaying your previously used addresses.
No. But it may be a problem identifying each payment (the labels in your wallet won't be restored) and your privacy (each one of the 200 people who paid you can now see the 199 other payments that belong to you).
Maybe the user has forgone privacy to reduce future transaction fees by payment batching and utxo consolidation.