Wow, that's a loaded post, (the OP post). But ... on the washers and caps, I assume you have presta valves? And the "washers" are the "nuts" that go over the valve and screw down to the rim? Well, the "washers" and caps are the first thing I throw out. They really are not needed ... unless you ride in muddy environments. You can really do without. But, as bkaapcke said, they really don't want your business. Look for another shop.

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I recently took a new internet purchased bike into a shop near where I grew up. It used to be a really highly regarded pro shop. I asked for a check-over and adjustment. They did a crappy job. When they didn't have time for a pro fit, I went elsewhere and got better service. But ... I'm starting to re-think my attitude about this shop. They did, on two occasions recently, order some small Shimano parts for me. The first time was an 11-tooth sprocket and lock ring so I could change my cluster to an 11-27 instead of a 12-27. Then, last week, they ordered some small spacer washers that go on the Shimano crank arms, and were not supplied on my bikes. Even though small-time orders, they ordered them for me.

Maybe you can just purchase little stuff from them, until they get to know you better. Then, if needed, you can try the service department again.