Why is my Transit Card (Clipper) not automatically on my Apple Watch?

I have an iPhone and Apple Watch with latest OS updates. My iPhone has some credit cards and also a Clipper transit card. The credit cards automatically are on my watch, but the transit card does not show up on my watch. It asks me to "transfer" the card, but I would like it to be on both. Why is there a different behavior here compared to credit cards and can I have it on both devices synced?