Where is the money to build the infrastructure if Telecom companies have to pay billions for the 5G spectrum?

    Source: The Economist. Gett Images

I am bewildered to see the telecom companies (Telcos) have to pay billions of dollars for the spectrum to the US government. At the same time, the government is telling everyone to build out the 5G infrastructure faster. If the telecom companies cannot charge more for the 5G service to their customers, where can they get the revenue to pay for the infrastructure after they spent most of their 5G budget on the spectrum? 

Wouldn't it make more sense for the government to charge less for the spectrum so the Telcos can build out the 5G infrastructure faster and generate more revenue and pay more tax to the government? What's your thought about this?

Why American telecoms firms are splurging on 5G spectrum

An auction of mobile frequencies is turning a blockbuster.

https://www.economist.com/business/2021/01/02/why-american-telecoms-firms-are-splurging-on-5g-spectrum