without UBI we can get these jobs done for a pittance, with UBI we're going to have to pay people more and improve their job satisfaction in order to get them done. — Pseudonym
And why would we not want to improve pay and job satisfaction? Millions of people devoting the better part of their waking hours to an unrewarding job (low pay, no satisfaction, and lots of stress) is a bad thing for the individual and society as a whole.
You are quite right that there would be knock-on costs above and beyond the pay out. The floor of acceptable pay and working conditions would rise, and should rise. Who can live working full time at the $7.25 minimum wage? That's about $15,000 a year, just $3000 above the federal poverty level for one person, and below the medicaid eligibility level, assuming the job was full time, which it probably isn't. Granted, people do eke out survival on wages that low, but in much of the country, and in most urban areas, it would be a grueling project.
Some states have minimum wage levels that are significantly higher than the federal level. Massachusetts and Washington have $11 MW. Some cities have set the minimum wage at $15, and some states are scheduled to reach $15 in a few years -- that's about $31,000 a year (if full time). There are, of course, places in the US where $31,000 is not enough to live well -- New York City, for instance, where rent for a small apartment can easily be more than $30,000 a year.
So, the UBI will affect the wage scale at the bottom. This will affect some industries much more than others, depending on what their pay structure is.
Most municipal and civil engineering workers are paid much more than a pittance to maintain the city: pick up garbage, maintain streets, keep the water and sewer working in good order, etc. A UBI would not come close to matching their wages and benefits.
There are many jobs that do not pay well, do not have good benefits, and have little or no security. Some of these are city, county, state, or federal government positions, but not many. Most of these are in the private sector. The temporary-work industry would be rather severely affected, I would think. So would child-care, retail, many non-unionized jobs, etc.