Actually a wheel bearing can be going bad without making noises.
If the wheel bearing has some play beyond spec or doesnt spin smoothly then its most likely going. Also the wheel bearing seals may have been shot or the whoever did the wheel bearings on you car tighthen them too tightly and wore out your bearings prematurely. When your wheels starting making noise then its usually too late.

You payed dealership prices for those parts not online prices and payed for labor prices.

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1986 300SDL, 211K,Dealership serviced its whole life
1991 190E 2.6(120k)
1983 300D(300k)
1977 300D(211k)