I was paid to fly. Now I have to pay to fly. Lack of funds… Getting old sucks and is not for sissies…
Your point is valid - a short flight can cost more per hour than would a powered aircraft.
But soaring clubs tend to have gliders that are fully depreciated and thus rent for as little as $30/flight (the wear and tear on a glider mostly comes during takeoff and landing - there is little “per hour” expense as would be the case with an engine). The cost of a tow varies a lot, but $30 for 2000’ is typical. At some sites (common in Europe, rare in the US) launching is done by ground tow or winch, which is really cheap (say, $5). On a halfway decent day, a flight of 3 hours would be easy (assuming you’re allowed to hog the club glider for that long).
It would be wrong to say this is typical - clubs vary a lot. Commercial operations would essentially always be substantially more expensive (but they won’t expect you to donate labor, as a club would).
So the final answer is “it depends” - you must shop around and hope there is a well-run club in your area.
I’d like to dissent from this, to some degree.
It’s certainly wise to assume that currency is valuable and a long layoff dictates the need for additional care (and perhaps some instruction). But safety in flying should rarely or never be a matter of reflexes.
As the old saying has it: “The superior pilot is one who uses his superior judgment to avoid any need of his superior skill.”
If anyone wanted to get into flying commercially, now is definitely a good time to do it. There is a pilot shortage that has reached levels unheard of in the last 30 years or so. As an example, the airlines in Australia have massive expansion plans and are running big recruiting drives. The regional turbo-prop airlines are getting sucked dry of pilots and there are not enough new ones coming in to fill the gaps. Australia is only training enough pilots to cover the retirement of old pilots but it is expected that we’ll need many more than that for several years to come.
After a couple of decades of steadily declining wages and conditions there has been a turn around and companies are competing to retain and attract what little pilots there are.
Twelve months ago the company I work for was paying a Dash 8 Captain $82,000 AUD and bases were at remote areas of the country. They are now paying $100,000 with a retention bonus of $50,000 1st year, $50,000 2nd year, and $100,000 3rd year. They are also offering “fly-in fly-out” from any Australian capital city as an alternative to the bonus if life style is your preference over money.
Minimum requirements for employment are going down. They used to require 1500 hours total time, now it is 1000 and there is pressure to further reduce it to 500 hours. They are also in the process of starting up a cadetship program where the company will fund flying training for new pilots.
Until recently the company would only employ Australian citizens, they will now employ from the UK, New Zealand, Canada, and South Africa.
Our HR and recruiting people used to be able to sit back and wait for job applications to roll in, now they are directly targeting specific individuals and running travelling roadshows to try and entice pilots to sign up.
Edit: No I don’t work for our recruiting department 
I learned to fly when I was stationed in Coronado, California in the mid-70s. A Cessna 150 went for $11/hr, a 172 was $16/hr, and instructors were $8/hr. I got my private ticket and instrument rating, and was about 4 hours away from my commercial (by this time I was in college at Purdue.) I’d been checked out in 6 or 7 different planes, including a retired Navy T-34B.
I was having a rough time in school, and I decided to go flying to unwind. Not smart. I was tooling along a bit north of West Lafayette, when I suddenly looked down and saw a small jetliner passing below me. It wasn’t at an unsafe distance from me, but I was disturbed that I hadn’t seen it approach or anything. That’s not a good thing.
I landed, and grounded myself. A year later, I graduated. Then I bought my first house. And the longer I was away from it, the less interested I was in getting current. October 1978 was the last time I flew. In some ways, I miss it, but my husband and I have a boat. We can’t afford 2 obscenely expensive hobbies.