We only have a fraction of the number of independent bike shops that we once had many decades ago, partly due to the interim decline in cycling and also very much due to multiple discount traders selling cheap bikes squeezing the small guys out of the market.
As such many small dealers are always overloaded with repair work and need to limit what they accept to ensure their own customers get a reasonable service. Taking on more staff often isn't an option, suitably qualified people are difficult to get and often cost more than the very limited margins from bike repairs.
As such, I see nothing wrong in a shop picking out particular repair groups to exclude in order to contain the amount of work they can support. Bikes not sold by them and the ease of identifying an e-bike as one of those makes them an obvious candidate. Attempting to cherry pick according to the nature of a repair will only result in angering further those still excluded by that means.
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