It's all made to look far, far too simple...
The reality of the situation is, if you have 4 or 5 bowlers who are capable of keeping the economy-rate tight (eg 3.7-3.8-an-over), you WILL keep your opponents to low totals. It doesn't matter if a team is 180\2 after 50 overs, that's far better than 260\9.
It's no use taking a wicket or two at the top of the innings, going for 5-an-over in your first 6 overs, then coming back at or near the death and taking another couple while going for 7-an-over. That doesn't help your team at all. But it looks good for your average when you get 10-58-4. And if you were to bowl well next spell and take, say, 10-37-3, then people would react "ah, see, wicket-taking is key". This is very typical of, for example, Brett Lee and James Anderson.
A more persuasive case for the opposition is Makhaya Ntini. Typically, his figures tend either to be 7-48-1 or 10-38-3. He either goes for plenty and poses little threat, or he takes wickets and keeps it relatively tight. THIS is more the sort of bowler you want, if you can't have the Pollocks, McGraths, Frasers whose good days vastly outnumber the bad and whose tactics to take wickets and bowl economically always go hand-in-hand.
However, if you have 4 Mark Ealham\Gavin Larsen type bowlers, you won't go far wrong. These types of bowlers will give you far more low totals to go after than will the Andersons of this World.
The trouble at the current time is that there aren't enough bowlers capable of bowling in that way. Too much emphasis is placed on bowlers who appear to be wicket-takers, but who in reality take few wickets and usually get belted to boot. One pertinent example is given in this poll - Sajid Mahmood couldn't exemplify the case better.
It shouldn't be ignored that the vast majority of the best ODI bowlers (Donald, de Villiers, Matthews, Dale, Fleming, Gillespie, Vaas, Wasim Akram, Gough, Caddick, Mullally) have been more than capable of bowling economically and taking wickets.
What should be patently obvious to even the non-Einsteins of this World, though, is that batsmen don't just happily plod along at 3.5-an-over for 40 overs - they make some sort of attempt to up the rate! And thereby often gift their wickets away without the need to bowl wicket-taking deliveries. One thing, though - bowling economically is about more than just bowling length. At some stage in a one-day game, you need to switch from standard-good-length to blockhole-length. Bowlers capable of doing that have always been precious, and there are very few around at the current time, meaning that if a side makes 180\3 off 40 overs they can have a decent chance of smashing 80-100 off the last 10, thereby making a decent total. But with good death-bowlers, 180\3 off 40 is much more likely than not to turn into 220\9 off 50 or maybe even 210ao off 46.
The only way taking wickets is going to be better than bowling economically is if you can bowl your opposition out for 190 off 38 overs.