a lot of people are complaining about the Giro D'Italia bike race happening in Israel right now.

The Giro D'Italia is one of the 3 prominent bike races in the world and for the first time ever they are starting the race outside the borders of Europe, specifically in Israel.

The 2 [main] complaints are:
1. Shabbos shouldn't take a hit for a cycling event, perhaps especially for a foreign event that really has nothing to do with us.
2. why should we be so inconvenienced by them with road closures and the like, especially as you can see by the numbers of people turning out to watch at the various stages, most people seem not to care too much about it.

Regarding Shabbos, I agree. chilul shabbos should not be excused for a cycling event. I am not sure how it is justified here and how the Haredi/Dati MKs let it happen with no significant protest. Perhaps because the chuilul shabbos was largely by non-Jews, with the police only securing the event as they are obligated to do as pikuach nefesh. I am not sure. It seems hard to justify, but it went down with nary a peep from the people in place to defend the honor of Shabbos, so perhaps they found a reason it is ok.

Regarding the logistics and social issues - that's part of living in a modern state. There are events that are deemed important enough that it is worth the governing authorities to close off roads or whatever else that is an inconvenience for some people. Sometimes it is a marathon or a cycling event, sometimes it is a commemoration of a local or global person worthy of recognition for something, sometimes it is a block party or a local business event or a hachnassat sefer torah or whatever.

These events are important. They raise awareness to whatever the event is honoring or recognizing. In this case, perhaps it raises awareness to the sport of cycling, and fitness in general. Maybe more people will take up cycling, or other forms of sport and exercise, and become healthier as a result. More than that, there is also world recognition of Israel and Jerusalem and the advancement of financial and commercial relationships with foreign companies and governments. And there are surely other important considerations. It is generally a minor inconvenience to the few for the greater good of the nation.

And, it is not fair to complain that so few people turn out to watch. With the first day of the event happening on a Friday, with a massive heat wave, perhaps people just didnt want to spend many hours standing outside in the oppressive heat. With the event also running through Shabbos, that left the entire religious public out of the picture. With Sunday being a ride from Beer Sheva to Eilat, that is a lot of empty land down south that just doesn't have enough people to be out there, and many probably dont want to spend hours going down south just to watch a few minutes of cyclists whizzing by for a few minutes. It also is not fair to compare the crowd turnouts in the tiny State of Israel, with little culture for such events to the millions that turn out for the race in countries like Italy and France and whatnot.

All that being said, it is worth noting that the Giro D'Italia race was founded by Italian biker Gino Bartali who helped save much of Italian Jewry during the Holocaust. Bartali was involved in saving some people directly, but he spent most of his time sneaking false documents and papers in the body of his bike under the guise of his training. Those papers saved thousands of Jews from falling prey to the Nazis. If you want more details, here is a BBC article about Gino Bartali, and it is easy enough to find more information about him and his efforts during the war. While his being a hero to the Jewish people does not justify chilul shabbos, honoring him does justify, along with the other justifications, a minor inconvenience of a few road closures and some traffic for a day or two.