Translation:There is quite a lot of sugar, isn't there?
In colloquial Japanese "ooi" often has a negative connotation without the addition of "sugiru" to mean "too many".
From Stack Exchange on comparing the usage of "ooi" and "takusan":
By extension, 多い comes with a meaning similar to "more than necessary". This is another meaning たくさん does not have:
10人ならいいけど、20人はちょっと多いですね。 10 people would be good, but 20 is a bit much.
あのさ、これ、多くない？ Hey, isn't this too much?
You cannot replace 多い with たくさん in the above examples, because たくさん lacks the ability to compare a quantity to a certain level.
多い (ooi) is a special adjective that requires a special structure.
From Living Language:
There’s a tricky adjective 多い(おおい ooi) in Japanese which means “many/much”. Why tricky? It’s because you cannot place a noun following this adjective.
For example, you CANNOT say, X 多い人がいます。Ooi hito ga imasu. (Intended meaning: There are many people.)
This is pretty strange because you can normally place a noun following an adjective like the following:
これは赤い本です。Kore wa akai hon desu. This is a red book.
So, 多い ooi is a special case where “ADJ + Noun” doesn’t work. However, you CAN use this adjective in the “Noun がga ADJ ですdesu” format.
Example: 人が多いです。Hito ga ooi desu. (There are many people.) (literal translation: “People are many.”)