What's the significance of "blu" in names in Italy???

I know blu is the color blue but why does it show up in so many names?

There is a Blu cafe in Pisa.  We stayed at the Garibaldi Blu hotel in Florence.  A quick Google search showed me lots more hotels - for example Radisson Blu - with blu in the name.

My husband and I are curious?  What's this about?

I wasn't entirely sure so I Googled it in Italian and found this significant (translated to English)

-Blue blood, about who belongs or descends from a noble family
-Fifa blue
-In another sense, from the color of the service or representative cars (autoblù or auto b.),
About means or subsidies assigned on the basis of questionable privileges.