The legislation does not "bite"
It's not my fault that the legislation that does exist is ineffectively applied!
I would far prefer it if there was a formal qualification required, and an effective regulatory body, as it remove the dross from the industry and stop people like you believing every estate agent was a thieving liar. Sadly there is little I can personally do to affect this, so we carry on as we are, and just hope that vendors choose to employ the reputable estate agents out there, not the ones who are dodgy and crooked.
That's worth £3k - really?
Most of my clients pay me substantially more than that, so they must see some value!
I'm not sure where to start if you think there's only "a couple of calls before completion."
The period post offer acceptance leading to contracts being exchanged can frequently be around 12 weeks, and is normally the most labour intensive part of the process. A tricky transaction can involve several dozen, if not hundreds of calls, over many weeks. A skilled estate agent can be the difference between a sale going through, and it falling through.
"artificially inflated by estate agents with "another bidder"
If the possibility that two different buyers can express interest and offer on the same property is such a far fetched scenario, then call the EAs bluff, don't increase your offer.
Remember it is a clear breach of the Estate Agents Act for the EA to invent another where none exists. Whilst I am not naive enough to believe it is something that never occurs, in my experience it is something incredibly rare, and unlike you I see no benefit to the EA. In fact anyone who did this with any frequency would quickly attract a bad name and cause damage to their business.