I don't think that is so bad. I mean if you are serious about the sport.
I personally count the steps I take in the day and keep a running count of surfaces and temperatures as well since these are critical determinants of the stress that these foot strikes take out of you. For outdoor walking I break it up into hard surface (streets, paved paths), running tracks, and soft surface (dirt paths, grass...). I count all indoor surfaces the same. Since I don't walk on indoor tracks I figure nearly every indoor surface is about the same. Then I also note the temperature - above or below 74 degrees farenheit.
For example, yesterday I had the following counts:
Outdoor hard, hot: 1766 steps
Outdoor hard, cool: 1232 steps
Outdoor soft, hot: 982 steps
Outdoor soft, cool: 1444 steps
Outdoor track, hot: 0 steps
Outdoor track, cool: 332 steps
Indoor, hot: 0 steps
Indoor, cool: 676 steps
Of course hard surfaces and hotter conditions stress the body more so I double the points for these. As long as I can keep my overall point total below 20,000 per day I find that I can train at an optimal level and still feel fresh. Going much above 20,000, especially on a consistent basis, and my overall training definitely begins to suffer.
Anyway, sorry for too much detail here, but the point is I don't think that what Webb is doing is really all that excessive. I mean if you are serious about your training it only makes sense to do whatever it takes.