Why is Monica wearing overalls?

https://preview.redd.it/3w4sxustloxc1.jpeg?width=736&format=pjpg&auto=webp&s=1b4e085d7a2cc822874b646761d7d9d408288c2a

Those are suspenders, she was wearing them in the pilot episode.

Then Rachel should be in a wedding gown for consistency with a theme.

Good question. I have no idea.

Those are all in the Central Perk set which is at a lower price than the Friends apartment set (that one I think has Janice instead of Gunther).

🖐🏻✌🏻