Hello. I’m Posting from Japan and I’m Japanese.
I’m answering your question.
My answer is YES. Yes and yes!
We will have 10days-off, from 4/30 to 5/6.
It means every tourist spots and transportation will be so crowded. Especially, Amusement parks like TDL.
Also accommodation and airplane tickets are very expensive because many locals go for travel during this 10days...
if you are planning to visit Japan, you should consider your destination carefully.

Never mind,
I think commerce will be affected also...
but it’s possible to prepare for it!
would you tell me what exact place or things are you worried about? Then I can gather information for you.
Thank you!

Sorry to butt in aanro I’ll be there at the same time. Miinajp, would the Sumitomo tower (specifically the restaurants) be open during that week ?

Hello, sartoric!
Are you talking about the tower in Shinjuku??
( I googled “Sumitomo tower” and it seems there are same name buildings...)
Sumitomo tower in Shinjuku has some restaurants. And they open during GW.
If you tell me the name of restaurant, I can give you accurate information.
If you want to know about other Sumitomo tower, please let me know. Then I will go get information.
Thank tou!

Hi miinajp, yes, the tower in Shinjuku. I don’t have a specific restaurant in mind, just somewhere with a view over the city. I’m guessing that the Tokyo metropolitan building may not be open due to the holidays, and was looking for an alternative that also had a viewing level open to the public. If we have to eat...oh well, I’m sure it will be yummy.

Thanks for your info, I’m so excited to be heading to Japan soon :)