It depends. There is no way for us to say whether those rowguid columns serve a function other than replication. If there is already a rowguid column on a table, merge replication will use the existing column rather than create a new one.

Additionally, if code has not been written carefully, you may have code that is doing "Select *" and expects all columns to be there even if it doesn't use them. so removing the column can cause bad code to break.

You should involve your engineering team, and it should be thoroughly tested in pre-production before you do it in production.