“Please came into my parlor, the spider said to fly. The tricky spider is clever enough. The spider knows fully well that the fly is anticipated to be caught and will prove a good meal for himself.
The sticky web clings to the fly and traps him while it does not cling to the spider. No, it is not a fact. The web dress cling to the spider too. The spider is very much “at home” in his own web. He knows his way around. The spider made sure that these would be “safe” threads to use, when the web was originally spun. The threads he could touch without sticking to them.
There are many kinds of silk produced by the spider. The sticky kind is used in the web to catch prey. There is also another non-sticky kind used in making spokes of the web. It is strong enough to support the web. The spider is aware of this, and avoids the sticky ones. He can do this because of a remarkable sense of touch possessed by the spider.