That would be OK, but on the other hand the guy who wanted a bike didn't necessarily want to pay as much.
The buyer could have walked away if he didn't like the price.
I just don't see why some fast-moving little bastard with special access should get to siphon all the value out of the transaction between us.
That's why you never put in orders at market. You always buy and sell with limit orders. If the order can be fulfilled at a price that you are willing to pay or accept then it happens. If not, the order remains active until the target price is reached and any other conditions, such as all or nothing (AON) or fill or kill (FOK), are satisfied. As a human investor, and not a computer, you prefer to have the price you want rather than certainty of execution at a certain time. You cannot win on timing, but you don't also have to lose on price. Will it be the end of the world if you cannot buy or sell at any given second? For most small investors the answer is almost certainly not which means that you can afford to be patient. That's your advantage. Let the high frequency traders pass their shares around like hot potatoes thousands of times per second, it's meaningless on time scales of months and years because the long term value of the investment will always trend back towards the long term value of the underlying business or asset.
It's because the consequences are far greater for us than past generations. We need the most optimal outcome just to get by.
Whether or not your order executed at $3.50 or $3.52 doesn't make a damn bit of difference over the long run. Learn the lessons of Warren Buffet and you will realize that the intense focus on high frequency trading is a tempest in a teapot for the long term investor.