If the government is corrupt or corruptible (and which aren't?) then "service everyone" isn't as objective as it seems.
Meanwhile you can just force all the collective carriers to post their prices and their profits publicly or threaten them with complete loss of license to operate. This has been effective in the past and allows for a more open system with many competitors rather than a state selected contractor.
I love how you throw in bidding as if we're not talking about the government giving a monopoly in exchange for guarantees (it's considered a public good). This exchange of guarantees has made energy one of the most stable long term investments in a way that other investments just aren't. Gee, why would anyone take that deal?
Go educate yourself.
And go read up on Chesterton's Fence.
governments will give utilities a monopoly but with requirements such as they must service everyone regardless of profitability or they get fined all to shit.