I recently added a view to a 3rd party application and thought it would be sensible to make it an Indexed View for performance reasons, so I created the view with the SCHEMABINDING option. However, the 3rd party application that updated the underlying base table stopped working and we had to remove SCHEMABINDING and the index from the view. I was told that SCHEMABINDING had made the base table read only, but I don't think this is the correct explanation. BOL didn't seem to suggest this could happen either.
I had a similar situation with a third party application -- when I looked at it closely, it turned out to be related to SET QUOTED IDENTIFIERS. This is not something you can fix at runtime, it has to do with the way their sprocs were saved/parsed.
You might want to check this out.
In my case, the vendor realized that their scripting process for writing upgrade code had left out the appropriate statement and they will eventually fix it. But first they had to understand/notice it <shrug>.
They also told me that they frown on schema-bound views because "what if they want to change their schema". There are two interesting things about this, for the purposes of our discussion:
*1 -- They also frown on our creating additional indexes on the base tables, and they don't create any. They also try to discourage any interop/integration efforts, for the same reasons. So this, globally considered, is a ridiculous attitude, IMHO. Beyond the obvious optimization reasons to do this, our dealing with the schema as it currently exists, in some manner -- whether for a report or other custom output, or interop with another enterprise app -- is not something that can be avoided because a vendor tells you it's going to cause an issue. No matter how many layers of abstraction you put on top of the base tables, if they change schema it's on your head to re-build your custom indexes, or whatever it takes. You can't just "not do it".
*2 -- I am really wondering if this is what your vendor meant by telling you the "base table was readonly". IOW, maybe somebody mis-repeated something to you, what they meant was "if you create a schema-bound view, it hampers our code because the structure of the table is readonly (not the data). For example, it's possible that they dynamically create and drop flag fields, or that the person who made the original statement was thinking long term, "the schema will be readonly when we upgrade".
Anyway, this may not be involved, but I thought I'd share.