Let me acknowledge that glyphosate is only the "Active Ingredient" listed on many herbicides, and that it's actually the unlisted adjuvants that we need to be concerned about. Unfortunately the regulations only require safety testing of the active ingredients even though the adjuvants have been found to be 1000 times more toxic. The only other dangerous ingredient in RoundUp that I know of is polyethoxylated tallowamine POE-15.
In an effort to avoid using glyphosate I did some research on how the kill weeds around ornamental landscape plants, pathways and driveways. I still and always will object to Glyphosate and 2-4-D being used on or near vegetable gardens.
Here are the methods I was able to discover:
Pulling weeds by hand, and sheet mulching. This is great for a small area
Zinc Sulfate mixed 1-1/8 oz per gallon will treat 4 sq ft. At $12 per 10 lbs this works out to about $0.35/sq ft. Yikes!
BurnOut Weed & Grass Killer made of a special blend of citric acid and clove oil and other patented synergistic components. If I try this product I'll post the results, but from what I've read this too only stunts the plant and leaves the roots to grow again. If you have used this I'd like to hear about your results.
Weed Dragon is a large propane torch. Reviews state that they are effective at temporarily removing the weeds, but repeated treatment will be required to eventually kill more persistent weeds. Attacking the weeds again several days later seems to be advised.
The Weed Dragon delivers a 400,000 BTU while the mini delivers 25,000 BTU. The later uses a small disposable tank, and is easily held by one hand where as the former uses a 20 gallon tank and is often accessorized with a cart. There is also a 2.5 gallon model that is worn like a back pack.
Apparently 1 gallon of propane will last about 1 hour depending on how high the flame is turned up. Not all models have a flame adjustment.
Vinegar, salt, & soap mixed at 1/2 gal vinegar, 1/2 cup salt, 1/2tsp liquid dish soap will also kill weeds. This mixture costs about $6.00/gal. I don't know what the application rate is supposed to be, but I used it as I would use Roundup. After several applications there was only a few blotches otherwise the plants were healthy.
I hate the idea of supporting Monsanto or any biotech bent on destroying the earth with GMO and toxic chemicals. But they do seem to have the only spray on products that will kill weeds. How poisonous these herbicides are is a matter of debate. During the past 30 years I've never been particularly careful about handling Roundup or 2-4-D, and I don't seem to have been affected, but I've had friends who were in Vietnam that were severely harmed by defoliants.
Of course I'm not advocating that we ingest it. Only a crazy person would do that right? Oh yeah our GM foods have been modified to resist Roundup and therefore hugh amounts of the stuff is sprayed on our food. This I object to, but spraying my driveway seems okay to me.
It seems too cruel but I may have to do my own experiments with Roundup. The group of good and natural folks I would like to be able to include myself in say that Roundup destroys the life in the soil. Somehow I doubt this. Over time, the glyphosate can be tied up by cations in the water or it can be biodegraded by bacteria.  By spraying the leaves of a plant, those chemicals are taken down into the roots and might poison some of the microbiology, but with all the bull that I've been feed about vinegar I simply don't trust the disinformation any longer.
Here's the thing. Don't make up the facts just to make you case. Some organic herbicides such as herbicidal soaps and oils have been found to be more harmful to aquatic life than Roundup. The EIQ (Environmental Impact Quotient ) of Roundup is only 15.3 (on a scale of 1 to 100). .
But don't tell me vinegar kills weeds and that it's just as good as Roundup because it's not.